An example of a vehicle seat of this type is known art taught by U.S. Pat. No. 6,152,533. In this art, a front portion of a seat cushion is connected to upper rail members of slide rails via links, and a rear portion of the seat cushion is connected to a seat back. That is, the seat cushion, the upper rail members, the links and the seat back may constitute a four-joints link mechanism. Further, the seat back is supported by a reclining device with respect to rear portions of the upper rail members of the slide rails.
In order to perform a tilt-down operation, the reclining device is unlocked so as to tilt the seat back forwardly. At this time, the four-joints link mechanism is operated, so that the seat cushion can be lowered toward a floor while the seat cushion moves forwardly. The seat back is folded on the seat cushion, so that the seat can be retracted in a folded condition.
In order to perform a walk-in operation, the reclining device is unlocked so as to tilt the seat back to a predetermined forwardly tilted condition. At the same time, slide lock devices of the slide rails are unlocked, so that the seat can be slid forwardly.
In the art taught by U.S. Pat. No. 6,152,533, when the seat back is tilted to the predetermined forwardly tilted condition in order to perform the walk-in operation, the four-joints link mechanism is operated as in the case of the tilt-down operation, so that the seat cushion moves forwardly. Thus, when the seat involved in the walk-in operation is a second row seat, a distance between a seat cushion of the second row seat and a first row seat can be closed up. Therefore, a forwardly sliding amount of the second row seat can be reduced by an amount corresponding to the closed up distance. As a result, ease of getting in and out a third row seat can be reduced.
Thus, there is a need in the art to prevent a forwardly sliding amount of a seat from being reduced when a walk-in operation is performed while a tilt-down operation can be conventionally performed.